Spencer g



S. G. NEAL.

AIR RETAINING VALVE FOR AIR BRAKE APPARATUS.

APPLICATION FILED NOV; I8, 1916- RENEWED JUNE 7,1919.

Patented Sept. 2, 1919.

' UNITED STATES PATENT omen.

srmrcnn a. men, or NEW YORK, 1v. Y., ASSIGNOB, BY rmsnn essrcmms," 'ro nn'romrrc srneronr AIR BRAKE comm, or wmumo'ron, nnnawann,

a conromrron or DELAWARE.-

.lBr-BETAINING VALVE FOB AIR-BRAKE APPARATUS.

- Specification of Letters Patent.

Patented Sept. '2, 1919.

Application filed November 18, 1916, Serial ll'o. 131,994. Renewed June 7, 1919. Serial 1T0. 802,880."

To all whom it may concern:

Be it known that I, SPENCER G. NEAL, a citizen of the United States, and residing in the borough of Manhattan, city, county, and State of New York, have invented certain new and useful Improvements in Air-Re- No. 1,183,103, dated May 16, 1916, and No.

1,157,954, dated October 26, 1915. The air retaining valve shown and described in said patents places the train pipe reservoir 1n L communication with the train pipe during all service applications of the brakes, and means are provided whereby when the brake cylinder pressure is equal to or above tram pipe pressure, orwhen, after an equalization of train pipe and brake cylinder pressures, the brake cylinderpressure leaks down below the train pipe pressure and augmenting reservoir pressure, the augmenting reservoir will be sealed against communication with the train pipe, and placed in communication with the brake cylinder so that the said reservoir capacity will be added to the brake cylinder capacity and disconnected from the train pipe.

In the present invention the augmenting or train pipe reservoir is in communication with the train pipe during all service applications of the brakes,but upon an emergency application of the brakes t e train pipe reservoir is .disconnected from the train pipe and sealed.

The main object of the invention is to provide a retaining valve which will be operated by the service reservoir pressure to seal the train pipe reservoir from the train pipe upon a reduction of the train pipe pressure suflicient to secure an emergency application of the brakes. It is desirable, upon a reduction of train pipe pressure, to secure an emergency application of the brakes, to reduce the train pipe capacity by sealing the J train pipe reservoirs or disconnecting them train p'pe air throughout the length of the tram in emergency applications. Z

In the drawmg, Figure 1 is a vertical central sectional view of the air retaining valve; and

Fig. 2 a view similar to'Fig. 1, showing a slightly modified method of controlling the operation of the valve.

The train pipe or augmenting reservoir is connected to the triple valve through the 're-' taining valve for all service applications of the brakes, precisely as shown anddescribed in Patent No. 1,157,954. This valve consists of an outer main casing 1 forming a large train pipe chamber 2, said chamber being connected to the train pipe through pipe connection 4. The upper wall of the chamber 2 is formed by a flexible diaphragm or movable abutment 5, which is clamped in position by the upper part 6 of the casing, said part forming an upper controlling chamber 7 above the diaphragm. The train pipe reservoir is connected to the lower end of the retaining valve by means of a pipe connection 8 opening into a chamber .9 formed by a cap 10 screwed on the lower end of the main casingl. 3 v i Extending upwardly through the bottom of the valve casing 1 and into the chamber 2, is an open-ended tubular post 11 having a valve 12 formed at its upper end. rSl-iding on this post is a sleeve 13 carried by the diaphragm 5 and adapted to be seated on and unseated from the valve 12 by the variations pipe chamber 2 through the aperture 17, so

that when the valve seat 15Lisraised above the valve 12 on the upper end of the tubular post 11, chamber 2 will be in free communication with the train pipe reservoir and with the chamber 7. Within the chamber 2 is arranged a'coil spring 18, said springbean ing on the bottom wall of said chamber, and on the under side of the diaphragm-5, and

i. so

tending to scparatethe valve seat "15 and valve 12 and to maintain the train .pi" chamber 2 in communication with the'tram pipe reservoir.

briefly described as follows:

Upon a sudden and prolonged reduction in train pipe pressuresufiicient to secure the emergency application of the brakes, the

pressure in'chaniber 2 will be sufiiciently reduced to permit the air in chamber 7 to depress diaphragm and bring the seat of sleeve 13' down 'to valve 12,1therebyfclosing communication between the train pipe reservoir and the chamber 2. The reduction in pressure in chamber2 in an emergency application of the brakes, will take place more rapidly than "air canfiowf fronr chamber 7 into chamber 2', sothat the suv perior pressure in chamber '7 will depress diaphragm5. It is mani fest that by'means oftheair retaining valve shown in Fig. 1,,

thetrain pipe reservoir will be discons of the brakes. During all service applications of the brakes, however, thereductionfl of pressure in chamber 2 willbe comparatively slow, therebypermitting an equaliza tion of pressures in chambers 7 and 2 and 7 :upon valve 12. The spring 18 maintains the f diaphragm 5 in its upper position until there only occur when the pressure in chamber 2 is reduced suddenly sufficient to secure the emergency operation ofthe retaining valve.

A preponderance of pressure inchamber 7 will seal thetrain pipe reservoir from i the train pipe, upon of the brakes.

4o t v In the construction of valve shown in Fig.

1 2 the operation is precisely the same as in. thevalve illustrated in Fig.1. In the consjtruction shown in Fig. 2 thetrain pipe reservoir air passes tothe chamber 7 through a port 24 in the valve casing, the diaphragm 5 beingformed without the central apertures shown in Fig. 1. I

What'I claim is:

. means therein adapted to maintain a train pipe in communication with a train pipe reservoir during allslow 'variationsin train pipe pressure, said means being operated by tram p1pe reservoir air upon a sudden re-' ductlon in train p1pe pressure to seal the train pipe reservo r from the train pipe to reventj the train pipe reservoir pressure owering with the train ipe pressure.

2. A retaining valve i he operation of the apparatus may I I train p1pe reservoir, means carried by the diaphragm to control communication beingly maintaining open communication be- 1 tween the train pipe reservoirandtrain pipe chamberand the controlling chamber dur- .ing"all slow variations in train pipe pres- "sure, said means bein [operated by train ipe reservoir air in t e controlling champreventing the seating of the valve seat 15" an emergency application or air brake appalratus comprising a casing, a diaphragm vwithin said casing and dividing it into a to be connected to a train pipe and to a den reductionfin train pipe pressure the train pipe reservoir pressure in the controlling c amber. will move thediaphragm and seal said train pipe reservoir from the train pipech'amber.

3. 'A retaining valve for air brake apparatus comprising a casing, a diaphragm within said casing and dividing it into a train pipe chamber and a controlling chamk I the train pipe chamber being adapted nectedrfrom the train pipe so that the air: from said. reservoir cannot flow 5 into 4 the train pipe upon an emergency applicatiom to be connected to the train pipe and. to the train pipe reservoir, and means for yieldr upon a'sudden reduction in train pipe pressure to seal thetrain pipe reservoir from 1 thetrain pipe chamber and tomaintain open is a material preponderance of pressure in; chamber 7. The excessive. pressure in chame ber 7 must'be suflicient. to overcome spring 18, and this preponderance of pressure will ling chamber andthe train pipe chamber.

4. A retaining'valve for air brake apparatus com rising a casing, a diaphragm within sai casing and dividing it into a traint'fiipe chamber and a controlling chambet, I in open communication'with the train pipe reservoir, and means in the train pipe chamber to'yieldingly hold the diaphragm in posie controllingchamber being always tion to maintain open commumcation between the train pipechamber' and the train pipe reservoir during all slow variations of pressure in the train pipe chamber,the train ipe reservoir airin the controlling chamer moving said diaphragmto seal the con- I p nection between the train pipe .reservoin 1. Aretammg valve comprising a casing,

and theftrain pipe upon a sudden reduction of pressure in the train pipe chamber.

5. A retaining valve adapted to connect a train pipe reservoir with a train pipe during all slow variations in train pipe pressure and provided with means adapted to be operated by trainpipereservoir air upon a sudden reduetion of train pipe pressure to seal the train lpipe reservoir from the train pipe. 6. a

retainingvalveadapted to connect a; train p1pe reservoir with a train pipe during all slow variations in train pipe pressure and adapted upon a sudden reduction of train pipe pressure for an emergency application of the brakes to be operated, by train pipe reservoir air and to seal the train pipe reservoir from the train pipe to prevent the depletion of the train pipe reservoir air upon an emergency a plication of the brakes.

7. A retaining valve adapted to connect a train pipe reservoir to a train pipe for service applications of. the brakes and during all slow variations in train pipe pressure and operated by train pipe reservoir air upon a sudden reduction in train pipe pressure for an emergency application of the brakes to seal the train pipe reservoir from the train pipe to prevent the depletion of the train pipe reservoir upon an emergency application of the brakes.

8. A retaining valve for use in that type of air brake apparatus in which train pipe air is admitted to the brake cylinder for all service applications of the brakes and comprising a. casing, and means therein maintaining open communication between the train p-ipe reservoir and the train pipe dur ing all slow reductions in train pipe pressure for service applications of the brakes, said means sealing-the train pipe reservoir from the train pipe by train pipe reservoir air upon a sudden reduction of pressure in the train pipe chamber for securing an emergency application of the brakes whereby the train pipe reservoir will not be depleted during an emergency application of the brakes.

9. An air brake apparatus comprising a valve device adapted to maintain a train pipe in communication with a train pipe.

cations of the brakes, a valve device adapted to maintain the train pipe reservoir in communication with the train pipe during all slow variations in train pipe pressure but operating on a sudden reductlon in train pipe pressure to seal the tram pipe reservolr from the train pipe, and thereby reduce the volume of the train pipe and prevent the 7 train pipe reservoir pressure being lowered with the train pipe pressure.

In testimony whereof I hereunto afl'ix my signature.

SPENCER G. NEAL. 

